الفهرس 
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Abstract
Gum arabic (GA) refers to dried exudates obtained from the stems and branches of Acacia senegal (L) or Acacia seyal which grow principally in the African region of Sahe in Sudan. The crude exudate of GA is processed differently according to the quality finally required for it to be marketed. Air drying is the easiest method to be applied which, together with mechanical milling (kibbling), are used in order to produce a granular material that is much more soluble than the raw product. Other processing methods are spray drying and roller drying. Additionally, many studies have confirmed the effective biological role of GA including reduction in plasma cholesterol level in animals and humans, anticarcinogenic effect and antioxidant effect with a protective role against hepatic and cardiac toxicities. In addition to that, it has been claimed that GA alleviates effects of chronic renal failure in humans Also, GA is indigestible to both humans and animals, not degraded in the intestine, but fermented in the colon to give short-chain fatty acids, leading to a large range of possible health benefits. One of these benefits is its prebiotic effect. Four week supplementation with Gum Arabic (10 g/day) led to significant increases in Bifidobacteria, Lactobacteria, and Bacteriodes indicating a prebiotic effect. Several epidemiological studies suggest that a high intake of dietary fiber, including GA (dietary fiber >< 80%), is associated with beneficial effects on fat metabolism. It can serve to reduce obesity and therefore prevent associated complications in humans including coronary heart disease, stroke and diabetes. Also, arabic gum from acacia tree is able to modify rheological properties of doughs and thus improve the quality of the final bakery product. In the present study, the researcher, intend to explain in detail’s the chemical description, physicochemical properties, uses in an attempt to open up a 62 new horizon for the use of GA in an important food technological, nutritional and therapeutic applications. Also, there is substantial evidence that GA can play a positive health-related role in addition to its well-known properties as a food additive is also discussed. The obtained results could be summarized as follow: The contents of moisture, total protein, crude fat, ash and total soluble fiber of GA collected from Sudan Republic were 11.21, 2.30 0.13, 2.95 and 83.41%, respectively. Results indicated that the moisture content of Sudanese gum is significantly (p < 0.05) lower than the value reported by FAO, (1990). Total protein (2.30, T.N. 0.37%) and ash value (2.915%) are falls within the range reported by FAO, (1990 The results of farinograph measurements (Table 3 and Figure 1 show the influence of GA on the qualitative properties of the wheat flour dough, which are important during its processing. The results reveal that the control dough sample (without the addition of GA) has a significant higher absorption than the samples of dough with the additions of GA and also that with the increasing amount of GA the absorption is gradually decreasing The extensograph results of wheat flour control dough and dough’s with additions of GA. Dough strength (Extensibility) determined by the area under the curve and is proportional to energy needed to bring about rupture. The results reveal that the control dough sample (without the
addition of GA) has a significant lower extensibility than the samples of dough with the additions of GA and also that with the increasing amount of GA the extensibility is gradually increasing. Dough resistance to extension in B.U. is the most important index for dough ability to retain gas. Addition of GA to flour samples showed markedly increasing resistance to extension than the control samples (without the addition of 63 GA) and also that with the increasing amount of GA the resistance to extension is gradually increasing Chemical analysis of the dough with the addition of arabic gum from acacia tree indicated that with the increasing addition of GA, the
value of dry matter in the sample was decreasing in comparison with the control sample. The difference between the lowest addition (0.5 g.100g-1 GA) and the control sample is not significant but the opposite direction was observed with the highest concentration 0.4 g.100g-1, resulted in a difference of 5.73 % in comparison with the control sample.